CN111492029B - Encapsulation composition - Google Patents

Abstract

The present application relates to a composition for encapsulating an organic electronic component and an organic electronic device including the same, and provides an encapsulation composition that can form an encapsulation structure capable of effectively blocking water or oxygen introduced into an organic electronic device from the outside, thereby ensuring the lifetime of the organic electronic device and achieving durable reliability of the encapsulation structure at high temperature and high humidity and having high shape retention characteristics, and an organic electronic device including the same.

Description

Encapsulation composition

Technical Field

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority based on Korean Patent Application No. 10-2017-0174041, filed on December 18, 2017, the disclosure of which is incorporated herein by reference in its entirety.

Technical Field

The present application relates to a composition for encapsulating an organic electronic element, an organic electronic device comprising the composition, and a method for manufacturing the organic electronic device.

Background Art

An organic electronic device (OED) means a device including an organic material layer that generates alternating current of charges using holes and electrons, and examples thereof may include a photovoltaic device, a rectifier, an emitter, an organic light emitting diode (OLED), and the like.

The organic light emitting diode (OLED) in the above-mentioned organic electronic device has lower power consumption and faster response speed than the existing light source, and is conducive to making the display device or lighting device thinner. In addition, OLED has space availability, so it is expected to be applied to various fields covering various portable devices, monitors, notebook computers and TVs.

In the commercialization and application expansion of OLED, the most important issue is the durability issue. The organic materials and metal electrodes contained in OLED are very easy to be oxidized by external factors such as moisture. Therefore, products including OLED are highly sensitive to environmental factors. Therefore, various methods have been proposed to effectively block oxygen or moisture from penetrating into organic electronic devices such as OLED from the outside.

Summary of the invention

Technical issues

The present application provides an encapsulation composition and an organic electronic device comprising the same, wherein the encapsulation composition can form an encapsulation structure that can effectively block water or oxygen introduced into the organic electronic device from the outside, thereby ensuring the life of the organic electronic device and achieving durable reliability of the encapsulation structure under high temperature and high humidity and having high shape retention characteristics.

Technical Solution

The present application relates to an encapsulation composition. The encapsulation composition can be an encapsulation material applied to seal or encapsulate an organic electronic device such as an OLED. In one example, the encapsulation composition of the present application can be applied to at least one side of a sealed or encapsulated organic electronic element to form an encapsulation structure. Therefore, after the encapsulation composition is applied to the encapsulation, it can be present at the periphery of the organic electronic device.

In this specification, the term "organic electronic device" means a product or device having a structure including an organic material layer between a pair of electrodes facing each other, which generates an alternating current of charges using holes and electrons, and examples of organic electronic devices may include but are not limited to photovoltaic devices, rectifiers, emitters, and organic light emitting diodes (OLEDs), etc. In one example of the present invention, the organic electronic device may be an OLED.

An exemplary composition for encapsulating organic electronic components may include an olefin-based resin, a curable oligomer, and a curable monomer. Relative to 100 parts by weight of an olefin-based resin, a curable oligomer may be included in an amount of 20 to 90 parts by weight, 22 to 70 parts by weight, 25 to 50 parts by weight, 26 to 45 parts by weight, 29 to 40 parts by weight, or 30 to 38.5 parts by weight. Here, the curable oligomer may be a compound having a glass transition temperature of 55°C or less, 50°C or less, 30°C or less, 0°C or less, -10°C, -18°C or less, -25°C or less, -30°C or less, or -40°C or less after curing, wherein the lower limit is not particularly limited, but may be -100°C or higher. In an example, the composition of the present application may not include a curable oligomer having a glass transition temperature higher than 55°C, higher than 30°C, higher than 0°C, or higher than -10°C. In the encapsulation composition formulation of olefin-based resin, curable oligomer and curable monomer, the present application can achieve shape retention characteristics and moisture and heat durability under harsh conditions while achieving moisture barrier properties by controlling the content of curable oligomer and the glass transition temperature range.

In one example, the present application includes the hygroscopic agent described below in the encapsulation composition, wherein the hygroscopic agent means a material capable of removing moisture or oxygen by chemically reacting with moisture or oxygen that penetrates into the encapsulation structure. Typically, when the hygroscopic agent reacts with the moisture in the encapsulation structure, the volume expands as it reacts with the moisture, thereby generating stress. In addition, as described below, the encapsulation structure of the present application includes a large amount of hygroscopic agents in the periphery of the substrate on which the organic electronic element is formed, so when it does not have enough elasticity to alleviate the expansion stress caused by moisture adsorption, the encapsulation structure may be peeled off from the adhesive or the encapsulation structure may be damaged. Therefore, in the specific formulation of the encapsulation composition, the present application realizes the shape retention characteristics of the encapsulation structure while realizing moisture barrier performance and the durability under high temperature and high humidity under harsh conditions.

In the present specification, the glass transition temperature may be a physical property after curing. Unless otherwise specified herein, the glass transition temperature may mean the glass transition temperature after curing it at any temperature between 50°C and 300°C for 20 minutes to 200 minutes; the glass transition temperature after irradiating it with ultraviolet rays at an irradiation level of 1 J/ ^cm2 to 10 J/ ^cm2 ; or the glass transition temperature after ultraviolet irradiation followed by thermal curing.

In one embodiment of the present application, the olefin-based resin in the encapsulation composition may be an olefin-based resin containing one or more reactive functional groups. In one example, the olefin-based resin may be a hydrophobic resin and may have a water vapor permeability of 50 g/m ² ·day or less. Considering that the encapsulation composition of the present application is applied to seal or encapsulate organic electronic devices, it can provide excellent moisture barrier properties by including an olefin-based resin that satisfies the above water vapor permeability range. In this specification, "resin having a water vapor permeability of 50 g/m ² ·day or less" may mean a resin: in a state where the resin is prepared in the form of a film formed by a resin layer having any one of 5 μm to 100 μm, the water vapor permeability measured in the thickness direction of the film is 50 g/m ² ·day or less. The water vapor transmission rate is measured at 100°F and 100% relative humidity, and may be 50 g/m ² ·day or less, 40 g/m ² ·day or less, 30 g/m ² ·day or less, 20 g/m ² ·day or less, or 10 g/m ² ·day or less. The lower the water vapor transmission rate, the better the moisture barrier property may be exhibited, so the lower limit is not particularly limited, but may be, for example, 0 g/m ² ·day or 0.1 g/m ² ·day.

Specifically, exemplary olefin-based resins of the present application include olefin-based resins derived from a mixture of monomers, wherein the mixture may have at least an isoolefin monomer component or a multiolefin monomer component having 4 to 7 carbon atoms. Based on the total monomer weight, the isoolefin may be present, for example, in a range of 70 wt % to 100 wt % or 85 wt % to 99.5 wt %. The multiolefin-derived component may be present in a range of 0.5 wt % to 30 wt %, 0.5 wt % to 15 wt %, or 0.5 wt % to 8 wt %.

Isoolefins may be exemplified by, for example, isobutylene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, 1-butene, 2-butene, methyl vinyl ether, indene, vinyltrimethylsilane, hexene, or 4-methyl-1-pentene. Polyolefins may have 4 to 14 carbon atoms and may be exemplified by, for example, isoprene, butadiene, 2,3-dimethyl-1,3-butadiene, myrcene, 6,6-dimethyl-fulvene, hexadiene, cyclopentadiene, or piperylene. Other polymerizable monomers, such as styrene and dichlorostyrene, may also be homopolymerized or copolymerized.

In the present application, the olefin-based resin may include an isobutylene-based homopolymer or copolymer. As described above, the isobutylene-based olefin-based resin or polymer may mean an olefin-based resin or polymer containing 70 mol% or more of a repeating unit derived from isobutylene and one or more other polymerizable units.

In the present application, the olefin-based resin can be butyl rubber or branched butyl rubber. Exemplary olefin-based resins are unsaturated butyl rubbers, such as copolymers of olefins or isoolefins and polyolefins. As olefin-based resins included in the encapsulation composition of the present invention, poly(isobutylene-co-isoprene), polyisoprene, polybutadiene, polyisobutylene, poly(styrene-co-butadiene), natural rubber, butyl rubber and mixtures thereof can be exemplified. The olefin-based resins that can be used in the present application can be prepared by any suitable method known in the art, and the present invention is not limited by such methods for preparing olefin-based resins.

In one example, the olefin-based resin can be a low molecular weight polyisobutylene resin. For example, the weight average molecular weight of the olefin-based resin can be 100,000 g/mol or less, less than 100,000 g/mol, 90,000 g/mol or less, or 70,000 g/mol or less, and the lower limit can be 500 g/mol or more, or 55,000 g/mol or more. By controlling the weight average molecular weight of the olefin-based resin within the above range, the present application can realize an encapsulation composition suitable for application and packaging processes. The encapsulation composition can have a liquid phase form and can be appropriately applied to the side encapsulation application of the organic electronic device described below.

The reactive functional group contained in the olefin-based resin may be a polar functional group. In addition, the reactive functional group may be reactive with the above-mentioned curable oligomer and/or curable monomer. The type of the reactive functional group is not particularly limited, but may be, for example, an anhydride group, a carboxyl group, an epoxy group, an amino group, a hydroxyl group, an isocyanate group, Oxazoline, oxetane, cyanate, phenol, hydrazide or amide. Examples of olefin-based resins with reactive functional groups can include succinic anhydride-modified polyisobutylene, maleic anhydride-modified liquid phase polyisobutylene, maleic anhydride-modified liquid phase polyisoprene, epoxy-modified polyisoprene, hydroxyl-modified liquid phase polyisoprene or allyl-modified liquid phase polyisoprene. When such olefin-based resins form a crosslinked structure with the above-mentioned curable oligomers and/or curable monomers, the present application can achieve an encapsulation composition with desired physical properties such as moisture barrier properties and operability in the present application.

In an example, the encapsulation composition of the present application may include a curable oligomer. The oligomer may have one or more curable functional groups, or may have a multifunctionality having two or more curable functional groups. By including a curable oligomer, the present application makes it possible to maintain the elasticity of the encapsulation structure while supplementing the low thermal durability of conventional olefin-based resins under high temperature and high humidity.

The weight average molecular weight of curable oligomer can be in the range of 400g/mol to 50,000g/mol, 430g/mol to 30,000g/mol, 450g/mol to 10,000g/mol, 500g/mol to 8000g/mol, 800g/mol to 6000g/mol, 1000g/mol to 5000g/mol or 1500g/mol to 4000g/mol.By comprising the oligomer with the weight average molecular weight range, the application can realize the desired physical properties as side encapsulation material.In this specification, weight average molecular weight means the value of being converted into standard polystyrene measured by GPC (gel permeation chromatography).

In an example, curable oligomer can include at least one or more or two or more curable functional groups.Curable functional groups can include one or more thermosetting functional groups, such as epoxy, glycidyl, isocyanate, hydroxyl, carboxyl or amide, or can include functional groups curable by electromagnetic wave irradiation, such as carbamate, epoxy, cyclic ether, thioether, acetal or lactone.In one embodiment of the application, curable oligomer can include carbamate acrylate, silicone acrylate, aliphatic acrylate or polyester acrylate, but is not limited to this.In an example, considering the above-mentioned glass transition temperature range, curable oligomer can not include epoxy acrylate, but is not limited to this.

In one embodiment of the present application, as described above, the encapsulation composition may also include a curable monomer. The weight average molecular weight of the curable monomer may be less than 400 g/mol, 50 g/mol to 380 g/mol or 100 g/mol to 300 g/mol. When the encapsulation material is applied to a substrate on which an organic electronic component is formed, the present application achieves excellent application characteristics and processability by including a curable monomer. In addition, due to the inclusion of a curable monomer, the present application can prevent damage to the component by providing a solvent-free encapsulation composition.

In one example, the viscosity of the curable monomer as measured at a temperature of 25° C., a strain of 5%, and a frequency of 1 Hz may be 500 cP or less, or in the range of 50 cP to 300 cP. When applying the encapsulation composition to the periphery of the organic electronic element, the present application may ensure processability by including the curable monomer having the viscosity range.

The material of the curable monomer is not particularly limited, and may include, for example, an epoxy compound, an oxetane compound, or an acrylic monomer. The acrylic monomer may include a monofunctional acrylic compound or a multifunctional acrylic compound.

In an example, as curable monomer, aromatic or aliphatic or linear or branched epoxy compounds can be used. In one embodiment of the invention, epoxy compounds having an epoxy equivalent of 50g/equivalent to 350g/equivalent or 100g/equivalent to 300g/equivalent can be used comprising two or more functional groups. In the present application, as curable monomer, epoxy resins having a cyclic structure in its molecular structure can be used, and for example, alicyclic epoxy resins can be used. By having excellent compatibility with olefin-based resins or curable monomers, alicyclic epoxy resins can be cured without phase separation to achieve uniform crosslinking of the composition.

In addition, the linear or branched aliphatic epoxy compound may include aliphatic glycidyl ether, 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, propylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether or neopentyl glycol diglycidyl ether, but is not limited thereto.

In addition, as long as the oxetane-based compound as a curable monomer has an oxetane functional group, its structure is not limited, and it can be exemplified by, for example, OXT-221, CHOX, OX-SC, OXT101, OXT121, OXT221 or OXT212 from TOAGOSEI, or EHO, OXBP, OXTP or OXMA from ETERNACOLL.

In addition, as a curable monomer, the acrylic monomer may include polybutadiene dimethacrylate, 1,4-butanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,8-octanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, dicyclopentyl di(meth)acrylate, dicyclopentyl di(meth)acrylate, cyclohexane-1,4-dimethanol di(meth)acrylate, tricyclodecane dimethanol (meth)acrylate, dihydroxymethyl dicyclopentane di(meth)acrylate, neopentyl glycol modified trimethylpropane di(meth)acrylate, adamantane di(meth)acrylate, trimethylolpropane tri(meth)acrylate or a mixture thereof.

In one embodiment of the present application, the curable monomer may be included in an amount of 10 to 45 parts by weight, 12 to 43 parts by weight, 13 to 38 parts by weight, or 14 to 25 parts by weight relative to 100 parts by weight of the olefin-based resin. Within the above content range, the present application can improve the application characteristics of the encapsulation composition and achieve heat resistance retention.

In one example, the encapsulation composition may further include an inorganic filler. In order to control the thixotropy of the encapsulation composition, an inorganic filler may be included separately from the hygroscopic agent described below. The specific type of filler that can be used in the present application is not particularly limited, for example, one of silicon dioxide, calcium carbonate, aluminum oxide, talc, etc., or a mixture of two or more thereof may be used.

In the present application, in order to improve the bonding efficiency between the filler and the organic binder, a product surface-treated with an organic material may be used as the filler, or a coupling agent may be added thereto and used.

The encapsulation composition of the present application may include 0.1 to 30 parts by weight, 1 to 28 parts by weight, or 3 to 23 parts by weight of an inorganic filler relative to 100 parts by weight of an olefin-based resin. By controlling the content of the inorganic filler within the above range, the present application can provide an encapsulation material in which the expected encapsulation structure shape in the present application can be easily realized.

In addition, the BET surface area of the inorganic filler can be in the range of ^35m2 /g to ^500m2 /g, ^40m2 /g to ^400m2 /g, ^50m2 /g to ^300m2 /g or ^60m2 /g to ^200m2 /g. The specific surface area is measured using the BET method, and specifically, the specific surface area can be measured by adding 1g of the inorganic filler as a sample to the tube with ASAP2020 (Micromeritics, the United States) at -195°C without pretreatment. The average value can be obtained by measuring the same sample three times. By controlling the specific surface area of the inorganic filler within the above range, the present application can provide an encapsulation material in which the expected encapsulation structure shape in the present application can be easily realized.

In addition, in one embodiment of the present application, the encapsulation composition may include a curing agent if necessary. The curing agent may be a thermal curing agent or a photocuring agent. For example, a suitable type of curing agent may be selected and used according to the type of functional group contained in the olefin-based resin, curable oligomer or curable monomer, and one or more curing agents may be used.

In one example, in the case of containing an epoxy group, the curing agent is an epoxy curing agent known in the art, and for example, one or two or more of an amine curing agent, an imidazole curing agent, a phenol curing agent, a phosphorus curing agent, or an anhydride curing agent, etc., may be used, but is not limited thereto.

In one example, as a curing agent, an imidazole compound which is solid at room temperature and has a melting point or decomposition temperature of 80° C. or higher can be used. As such a compound, for example, 2-methylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, or 1-cyanoethyl-2-phenylimidazole can be exemplified, but it is not limited thereto.

In one embodiment of the present application, the curing agent may be a latent thermal curing agent, such as an imidazole-isocyanuric acid adduct, an amine-epoxy adduct, a boron trifluoride-amine complex, or an encapsulated imidazole. That is, in the present invention, light irradiation may be first performed in the curing step of the encapsulation composition to control the initial fluidity, and the curing agent may be completely cured as a latent curing agent in the final curing step after light irradiation.

The content of the curing agent can be selected according to the composition of the composition (e.g., the type or ratio of the resin). For example, the curing agent can be included in an amount of 1 to 100 parts by weight, 1 to 90 parts by weight, or 1 to 80 parts by weight relative to 100 parts by weight of the olefin-based resin. The weight ratio can be adjusted according to the type and ratio of the functional groups of the olefin-based resin, acrylic oligomer, or curable monomer, or the crosslinking density to be achieved.

In one embodiment of the present application, the encapsulation composition may include an initiator. As the initiator, for example, a cationic initiator or a photo radical initiator may be included.

In one embodiment of the present application, the encapsulation composition may include a cationic initiator or a free radical initiator.

The cationic initiator may be a cationic photopolymerization initiator, for example, As an ionized cationic initiator of a salt or organic metal salt series, or a non-ionized cationic photopolymerization initiator of an organic silane or latent sulfonic acid series. The salt-based initiator can be exemplified by diaryliodonium As the initiator of the organic metal salt series, examples include iron arenes, as the initiator of the organic silane series, examples include o-nitrobenzyl triarylsilyl ether, triarylsilyl peroxide or acyl silane, and as the potential initiator of the sulfuric acid series, examples include α-sulfonyloxy ketone or α-hydroxymethyl benzoin sulfonate, but are not limited to these.

The free radical initiator can be a photo radical initiator. The specific type of the photoinitiator can be appropriately selected in consideration of the curing rate and the possibility of yellowing. For example, a benzoin-based photoinitiator, a hydroxyketone-based photoinitiator, an aminoketone-based photoinitiator, or a phosphine oxide-based photoinitiator can be used, and specifically, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropane-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propane-1-one, 4-(2-hydroxy) ... 1-[4-(1-methylvinyl)phenyl]propanone], 2-[2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone], 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, and the like.

The content of the photo radical initiator can be changed according to the type and ratio of the functional groups in the radical photocurable compound, the crosslinking density to be achieved, etc. For example, the photo radical initiator can be compounded at a ratio of 0.1 to 15 parts by weight, 3 to 12 parts by weight, or 6 to 10 parts by weight relative to 100 parts by weight of the olefin-based resin. By including the photo radical initiator in the above content range, the present invention can introduce a suitable crosslinking structure into the encapsulation composition to achieve flow control at high temperature.

In an example, the initiator can include a cationic initiator and a free radical initiator at the same time, wherein relative to 100 parts by weight of an olefin-based resin, the cationic initiator can be included in an amount of 0.01 to 10 parts by weight, 0.01 to 5 parts by weight, 0.05 to 5 parts by weight, 0.1 to 4 parts by weight, 0.3 to 2 parts by weight, or 0.5 to 1.5 parts by weight, relative to 100 parts by weight of an olefin-based resin, the free radical initiator can be included in an amount of 3 to 12 parts by weight, 4 to 11 parts by weight, 5 to 10 parts by weight, 6 to 9 parts by weight, or 7 to 8 parts by weight. In an example, the free radical initiator content of the present application can be greater than the cationic initiator content. By controlling the above content range, the present application can achieve a suitable cross-linked structure in the encapsulation composition to improve heat resistance and durability at high temperature and high humidity.

The encapsulation composition of the present application may also include a hygroscopic agent. The term "hygroscopic agent" can be used to refer to a component that can adsorb or remove moisture or moisture introduced from the outside through a physical or chemical reaction, etc. That is, it means a moisture-reactive adsorbent or a physical adsorbent, and a mixture thereof is also available.

The moisture-reactive adsorbent chemically reacts with moisture, water, oxygen, etc. introduced into the resin composition or its cured product to adsorb moisture or humidity. The physical adsorbent can extend the migration path of moisture or humidity penetrating into the resin composition or its cured product to inhibit penetration, and can maximize the barrier properties against moisture or humidity through the matrix structure of the resin composition or its cured product and the interaction with the moisture-reactive adsorbent, etc.

In the present application, there is no particular limitation on the specific type of the available desiccant. For example, in the case of a moisture-reactive adsorbent, it may include one or a mixture of two or more of metal oxides, metal salts or _phosphorus pentoxide ( _P2O5 ), etc.; and in the case of a physical adsorbent, it may include zeolite, zirconia or montmorillonite, etc.

Here, specific examples of the metal oxide may include lithium oxide (Li ₂ O), sodium oxide (Na ₂ O), barium oxide (BaO), calcium oxide (CaO) or magnesium oxide (MgO), and examples of the metal salt may include sulfates such as lithium sulfate (Li ₂ SO ₄ ), sodium sulfate (Na ₂ SO ₄ ), calcium sulfate (CaSO ₄ ), magnesium sulfate (MgSO ₄ ), cobalt sulfate (CoSO ₄ ), gallium sulfate (Ga ₂ (SO ₄ ) ₃ ), titanium sulfate (Ti(SO ₄ ) ₂ ) or nickel sulfate (NiSO ₄ ); metal halides such as calcium chloride (CaCl ₂ ), magnesium chloride (MgCl ₂ ), strontium chloride (SrCl ₂ ), yttrium chloride (YCl ₃ ), copper chloride (CuCl ₂ ), cesium fluoride (CsF), tantalum fluoride (TaF ₅ ), niobium fluoride (NbF ₅ ), lithium bromide (LiBr), calcium bromide (CaBr ₂ ), cesium bromide (CeBr ₃ ), selenium bromide (SeBr ₄ ), vanadium bromide (VBr ₃ ), magnesium bromide (MgBr ₂ ), barium iodide (BaI ₂ ) or magnesium iodide (MgI ₂ ); or metal chlorates, such as barium perchlorate (Ba(ClO ₄ ) ₂ ) or magnesium perchlorate (Mg(ClO ₄ ) ₂ ), but not limited thereto.

In the present application, the hygroscopic agent (eg, metal oxide) may be compounded in the composition in an appropriately processed state. For example, a pulverization process of the hygroscopic agent may be required, and the hygroscopic agent may be pulverized using a method such as a three-roll mill, a bead mill, or a ball mill.

Relative to 100 parts by weight of olefin-based resin, the encapsulation composition of the present application may include a hygroscopic agent in an amount of 10 to 150 parts by weight, 35 to 120 parts by weight, 40 to 100 parts by weight, 45 to 90 parts by weight, 50 to 85 parts by weight, 55 to 80 parts by weight, 60 to 79 parts by weight, or 63 to 77 parts by weight. Since the encapsulation composition of the present application preferably controls the content of the hygroscopic agent to 10 parts by weight or more, the encapsulation composition or its cured product can exhibit excellent moisture and moisture barrier properties. In addition, when the content of the hygroscopic agent is controlled to 150 parts by weight or less to form a thin film encapsulation structure, it can exhibit excellent moisture barrier properties.

In one example, the average particle size of the hygroscopic agent can be in the range of 0.1 μm to 10 μm, 1 μm to 8 μm, 1.5 μm to 5 μm, or 1.5 μm to 3.5 μm. In the present application, unless otherwise stated, the particle size can be measured according to the D50 particle size analysis. The present application can include an excess of hygroscopic agent in the packaging structure, while improving the reactivity with moisture by controlling the particle size to improve the moisture barrier performance.

In one example, the encapsulation composition may be in a liquid phase at room temperature (e.g., at about 25° C.). In one embodiment of the present application, the encapsulation composition may be in a solvent-free liquid phase. The encapsulation composition may be applied to encapsulate organic electronic components, and specifically, may be applied to encapsulate the sides of organic electronic components. Since the encapsulation composition has a liquid form at room temperature, the present application may encapsulate organic electronic components by applying the composition to the sides of the components.

In one embodiment of the present application, a process of applying a liquid composition is performed on the sealing side of an organic electronic component, but conventionally, there is a problem that it is difficult to maintain a desired package shape because the composition has high fluidity after application. In one example, the present application performs pre-curing by irradiating the package composition applied at a desired position with light, so that final curing can be performed after controlling the fluidity. Therefore, the present application can keep the applied package composition in the desired package shape until final curing. That is, since the package composition includes the above-mentioned specific components, the present application can introduce a dual curing method, whereby flow control at high temperature is possible after applying the package composition.

In addition to the above configuration, the encapsulation composition according to the present application may include various additives within the scope that does not affect the above-mentioned effects of the present invention. For example, according to the desired physical properties, the resin composition may include a defoamer, a coupling agent, a tackifier, a UV stabilizer or an antioxidant, etc. in a suitable content range. In one example, the encapsulation composition may also include a defoamer. By including a defoamer, the present application can achieve defoaming properties in the process of applying the encapsulation composition to provide a reliable encapsulation structure. In addition, the type of defoamer is not particularly limited, as long as the physical properties of the encapsulation composition required in the present application are met.

In one example, the encapsulation composition may be a pressure-sensitive adhesive composition or an adhesive composition. Therefore, the encapsulation composition may also be used as a structural adhesive for attaching a substrate having an organic electronic element formed thereon and a cover substrate to the element.

The present application also relates to an organic electronic device. As shown in FIG1 , an exemplary organic electronic device may include a substrate 21; an organic electronic element 23 formed on the substrate 21; and a side encapsulation layer 10 formed on the periphery of the substrate 21 to surround the side surface of the organic electronic element 23 and containing the above-mentioned encapsulation composition. In addition, the exemplary organic electronic device may also include a top encapsulation layer 11 covering the entire surface of the organic electronic element 23.

The top encapsulation layer and the side encapsulation layer may exist on the same plane. Here, "same" may mean substantially the same. For example, on the same plane, substantially the same means that the error in the thickness direction may be within ±5μm or ±1μm. The top encapsulation layer may encapsulate the upper surface of the element, and the side surface and the upper surface may be sealed together. The side encapsulation layer may be formed on the side surface of the element, but may not directly contact the side surface of the organic electronic element. For example, the top encapsulation layer may be sealed to directly contact the upper surface and the side surface of the element. That is, in a plan view of the organic electronic device, the side encapsulation layer may be located at the periphery of the substrate without contacting the element.

In the present specification, the term "periphery" means an edge portion of a periphery. That is, the periphery of a substrate herein may mean an edge portion of a periphery in a substrate.

The material constituting the side encapsulation layer is not particularly limited, but may include the encapsulation composition as described above.

On the other hand, the top encapsulation layer may include an encapsulation resin, wherein the encapsulation resin may be exemplified by an acrylic resin, an epoxy resin, a silicone resin, a fluororesin, a styrene resin, a polyolefin resin, a thermoplastic elastomer, a polyoxyalkylene resin, a polyester resin, a polyvinyl chloride resin, a polycarbonate resin, a polyphenylene sulfide resin, a polyamide resin or a mixture thereof. The components constituting the top encapsulation layer may be the same as or different from the components of the encapsulation composition as described above. However, since the top encapsulation layer is in direct contact with the element, the top encapsulation layer may not include the above-mentioned desiccant or may include a small amount of the above-mentioned desiccant. For example, relative to 100 parts by weight of the encapsulation resin, the top encapsulation layer may include 0 to 20 parts by weight of the desiccant.

In one example, the organic electronic element may include a reflective electrode layer formed on a substrate, an organic layer formed on the reflective electrode layer and including at least a light emitting layer, and a transparent electrode layer formed on the organic layer.

In the present application, the organic electronic element 23 may be an organic light emitting diode.

In one example, the organic electronic device according to the present application may be a top emission type, but is not limited thereto and may be applied to a bottom emission type.

Organic electronic components can also include a protective film (passivation film) for protecting the electrode between the top encapsulation layer or the side encapsulation layer and the electrode of the element. The protective film can be in the form of an alternating laminated organic film and an inorganic film. In an example, the inorganic film can be one or more metal oxides or nitrides selected from Al, Zr, Ti, Hf, Ta, In, Sn, Zn and Si. The thickness of the inorganic film can be 0.01 μm to 50 μm or 0.1 μm to 20 μm or 1 μm to 10 μm. In an example, the inorganic film of the present application can be an inorganic material that does not contain a dopant, or can be an inorganic material containing a dopant. The dopant that can be doped is selected from one or more elements of Ga, Si, Ge, Al, Sn, Ge, B, In, Tl, Sc, V, Cr, Mn, Fe, Co and Ni, or the oxide of the element, but is not limited thereto.

The application also relates to a method for producing an organic electronic device.

In one example, the manufacturing method may include applying the encapsulation composition on the periphery of the substrate 21 on which the organic electronic element 23 is formed to surround the side surface of the organic electronic element 23. The step of applying the encapsulation composition may be a step of forming the side encapsulation layer 10 as described above.

Specifically, the step of forming the side encapsulation layer may include the step of applying the above-mentioned encapsulation composition to surround the side surface of the organic electronic element 23, and may also include the step of curing the encapsulation composition. The step of curing the encapsulation composition may include the step of irradiating the encapsulation composition with light and/or the step of applying heat. In one example, the encapsulation composition may be cured by only one light irradiation step, but is not limited thereto, and may include a pre-curing step and a final curing step. The pre-curing step may include irradiating the encapsulation composition with light, and the final curing step may include irradiating the encapsulation composition with light or applying heat.

Here, the substrate 21 on which the organic electronic element 23 is formed can be formed by forming a reflective electrode or a transparent electrode on the substrate 21, such as glass or a film, via a method such as vacuum deposition or sputtering, and forming an organic material layer on the reflective electrode to manufacture. The organic material layer may include a hole injection layer, a hole transport layer, a light-emitting layer, an electron injection layer and/or an electron transport layer. Subsequently, a second electrode is further formed on the organic material layer. The second electrode may be a transparent electrode or a reflective electrode. Then, the above-mentioned side encapsulation layer 10 is applied to the periphery of the substrate 21 to cover the side of the organic electronic element 23. At this time, the method for forming the side encapsulation layer 10 is not particularly limited, and the above-mentioned encapsulation composition can be applied to the side of the substrate 21 using a method such as screen printing or a dispenser. In addition, a top encapsulation layer 11 for encapsulating the entire surface of the organic electronic element 23 can be applied. As a method for forming the top encapsulation layer 11, methods known in the art can be applied, and, for example, a droplet injection (one drop filling) method can be used.

In addition, in the present invention, a curing process can also be performed on the top encapsulation layer or the side encapsulation layer for sealing the organic electronic element, wherein the curing process (final curing) can be performed, for example, in a heating chamber or a UV chamber, and preferably in both. The conditions during the final curing can be appropriately selected in consideration of the stability of the organic electronic device, etc.

In one example, after applying the above-mentioned encapsulation composition, the composition can be irradiated with light to cause crosslinking. The light irradiation can include irradiating the encapsulation composition with light having a wavelength range of the UV-A region band at a light amount of 0.3 J/cm ² to 6 J/cm ² or a light amount of 0.5 J/cm ² to 4 J/cm ^2. As described above, the encapsulation composition can be pre-cured by light irradiation to achieve a package structure shape that can become a basis.

In one example, the manufacturing method may include final curing of the pre-cured encapsulation composition after light irradiation. Final curing may also include thermally curing the encapsulation composition at a temperature of 40°C to 200°C, 50°C to 150°C, or 70°C to 120°C for 1 hour to 24 hours, 1 hour to 20 hours, 1 hour to 10 hours, or 1 hour to 5 hours. In addition, final curing may include irradiating the encapsulation composition with light having a wavelength range of the UV-A region band at a light amount of 0.3J/ ^cm2 to 6J/ ^cm2 or a light amount of 0.5J/ ^cm2 to 4J/ ^cm2 . The final curing of the encapsulation composition may be performed by a step of applying heat or a step of irradiating the encapsulation composition with light.

Beneficial Effects

The present application provides an encapsulation composition and an organic electronic device comprising the same, wherein the encapsulation composition can form an encapsulation structure that can effectively block water or oxygen introduced into the organic electronic device from the outside, thereby ensuring the life of the organic electronic device and achieving durable reliability of the encapsulation structure under high temperature and high humidity and having high shape retention characteristics.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view showing an organic electronic device according to one example of the present invention.

[Explanation of Reference Numerals]

1: Encapsulation composition

10: Side encapsulation layer

11: Top encapsulation layer

21: Base

22: Cover the base

23: Organic electronic components

DETAILED DESCRIPTION

Hereinafter, the present invention will be described in more detail through Examples according to the present invention and Comparative Examples not according to the present invention, but the scope of the present invention is not limited by the following Examples.

Hereinafter, in the examples and comparative examples, as olefin-based resins, anhydride-modified polyisobutylene resins (BASF, Glissopal SA, hereinafter referred to as PIBSA) are used. As difunctional (multifunctional) curable oligomers, epoxy acrylates (Sartomer, CN110, Tg 60°C), urethane acrylates (Sartomer, CN9021, Tg-54°C) and flexible epoxy resins (Epiclon-EXA-4816, hereinafter referred to as EXA4816, Tg-20°C) are used, and as curable monomers, alicyclic epoxy resins (Daicel, Celloxide 2021P, Mw: 250 g/mol, epoxy equivalent: 130 g/equivalent, viscosity 250 cP, hereinafter referred to as C2021P), monofunctional acrylates (SR420) and 1,6-hexanediol diacrylate (HDDA) are used. As an inorganic filler, fumed silica (Aerosil, Evonik, R805, particle size 10nm to 20nm, BET= ^150m2 /g) was used, and as a hygroscopic agent, calcium oxide (CaO, average particle size 8μm, Aldrich) was used. As a photoinitiator, a photocationic initiator (San-apro, CPI-101A) and a free radical initiator (TPO) were used.

Examples 1 to 4 and Comparative Examples 1 to 4

For the above composition, the components were compounded in the weight ratios shown in Table 1 below and introduced into a mixing container. The unit is parts by weight. In the mixing container, a uniform composition solution was prepared using a planetary mixer (Kurabo, KK-250s).

[Table 1]

Hereinafter, the properties of the encapsulating compositions prepared in Examples and Comparative Examples were evaluated in the following manner.

1. Elastic modulus measurement

The encapsulating compositions prepared in Examples or Comparative Examples were each formed into a 10 mm×30 mm rectangle (thickness 10 μm to 400 μm), and after UV irradiation (metal halide lamp 3 J/cm ² ), a specimen cured at 100° C. for 1 hour was prepared, and the upper and lower portions of the specimen were attached with 3M tape so that the center portion became 10 mm×10 mm.

The upper and lower tape parts of the manufactured specimen were fixed on a tensile machine, the length and width of the fixed specimen were loaded to 10 mm×10 mm, and the force applied when stretched in the y-axis direction at a rate of 5 mm/min at 25° C. was measured.

The elastic modulus is measured by substituting the slope within the initial stretching range of 5 mm of the measurement graph (X axis: specimen major axis length, Y axis: force applied during stretching) into the following equation (slope, specimen major axis/minor axis length and specimen thickness are substituted).

The measurement was performed using a TA (Texture Analyzer)-XT2 plus instrument, and the measurement time was stopped when the specimen was broken.

The elastic modulus was calculated by substituting the slope of the measurement graph into the following equation.

[Equation 1]

E = slope × (length/(width × thickness))

2. Elongation measurement

In the graph for which the elastic modulus measurement is completed, calculate the ratio of the elongated length of the specimen at break to the initial length.

Elongation (%) = ΔL/L ₀ × 100

ΔL means the elongation length of the long axis of the specimen until the specimen breaks, and _L0 means the initial length of the specimen in the long axis direction.

3. Heat and moisture resistance

The encapsulation composition solution prepared in the example or comparative example was each applied to a 200 μm layer on 0.7T soda-lime glass using a coating bar. Then, a sample was prepared by laminating the layer with the same glass, irradiating the encapsulation composition with light having a wavelength range of the UV-A region band (metal halide lamp) at a light amount of 3 J/cm ² , and then applying heat thereto in an oven at 100° C. for 1 hour. Then, the sample was kept in a constant temperature and humidity chamber at 85° C. and 85% relative humidity for about 1000 hours.

In the case where there is no change in the inside and side of the coating area, the heat resistance measurement is represented as O, and in the case where a void occurs in the inside of the coating area, the heat resistance measurement is represented as X.

In the case where the moisture-penetrated area was not lifted, the moisture resistance measurement was indicated as O, and in the case where the moisture-penetrated site was lifted from the glass, the moisture resistance measurement was indicated as X.

4. Moisture barrier properties

Calcium was deposited to a size of 5 mm × 5 mm and a thickness of 100 nm on a glass substrate having a size of 100 mm × 100 mm, and the encapsulation compositions of the examples and comparative examples were each applied to the edge portion except for calcium. After laminating it with a cover glass having a size of 100 mm × 100 mm in a coated state, UV irradiation was performed using a metal halide light source at a light amount of 3 J/cm ² , and then heat was applied thereto in an oven at 100°C for 1 hour. The obtained sample was observed in a constant temperature and humidity chamber at 85°C and 85% relative humidity to observe the time at which calcium began to become transparent due to an oxidation reaction caused by moisture penetration.

[Table 2]

Claims (16)

1. A composition for encapsulating organic electronic components, comprising an olefin-based resin, a curable monomer, and a curable oligomer, wherein the curable low polymer is The polymer is included in an amount of 29 parts by weight to 90 parts by weight, and the curable oligomer has a glass transition temperature of 55° C. or lower after curing, wherein said olefin-based resin has at least one reactive functional group, wherein said curable oligomer contains one or more curable functional groups, The reactive functional groups include acid anhydride groups, carboxyl groups, epoxy groups, amino groups, hydroxyl groups, isocyanate groups, oxazoline, oxetanyl, cyanate, phenol, hydrazide or amide group, Wherein the curable functional group includes epoxy group, glycidyl group, isocyanate group, hydroxyl group, carboxyl group, amide group, urethane group, epoxy group, cyclic ether group, thioether group, acetal group or lactone group . 2. The composition for encapsulating organic electronic components according to claim 1, wherein the olefin-based resin has a weight average molecular weight of 100,000 g/mol or less. 3. The composition for encapsulating organic electronic components according to claim 1, wherein the weight average molecular weight of the curable oligomer ranges from 400 g/mol to 50,000 g/mol. 4. The composition for encapsulating organic electronic components according to claim 1, wherein the curable monomer has a weight average molecular weight of less than 400 g/mol. 5. The composition for encapsulating organic electronic components according to claim 1, wherein the curable monomer includes an epoxy compound, an oxetane compound, or an acrylic monomer. 6. The composition for encapsulating organic electronic components according to claim 1, wherein the curable monomer is included in an amount of 10 to 45 parts by weight relative to 100 parts by weight of the olefin-based resin. Inside. 7. The composition for encapsulating organic electronic components according to claim 1, further comprising an inorganic filler. 8. The composition for encapsulating organic electronic components according to claim 7, wherein the inorganic filler is included in an amount of 0.1 to 30 parts by weight relative to 100 parts by weight of the olefin-based resin. . 9. The composition for encapsulating organic electronic components according to claim 1, further comprising an initiator including a cationic initiator and/or a radical initiator. 10. The composition for encapsulating organic electronic components according to claim 9, wherein the initiator includes a cationic initiator and a radical initiator, wherein relative to 100 parts by weight of the olefin-based resin, the The cationic initiator is included in an amount of 0.01 to 5 parts by weight, and the radical initiator is included in an amount of 3 to 12 parts by weight relative to 100 parts by weight of the olefin-based resin. . 11. The composition for encapsulating organic electronic components according to claim 1, further comprising a hygroscopic agent. 12. The composition for encapsulating organic electronic components according to claim 11, wherein the hygroscopic agent comprises a moisture reactive adsorbent. 13. The composition for encapsulating organic electronic components according to claim 11, wherein the average particle size of the hygroscopic agent is in the range of 0.1 μm to 10 μm. 14. The composition for encapsulating organic electronic components according to claim 11, wherein the moisture absorbing agent is included in an amount of 10 to 150 parts by weight relative to 100 parts by weight of the olefin-based resin. . 15. An organic electronic device, comprising: a substrate; an organic electronic element formed on the substrate; and a side encapsulation layer formed on the periphery of the substrate to surround the side of the organic electronic element. surface and comprising the composition for encapsulating organic electronic components according to claim 1 . 16. A method for manufacturing an organic electronic device, comprising the step of applying the composition for encapsulating an organic electronic element according to claim 1 on a periphery of a substrate on which an organic electronic element is formed to surround The side surface of the organic electronic component and the composition for encapsulating the organic electronic component is cured.